Bone chapels, also known as ossuaries, are religious sites that house human skeletal remains. These chapels often serve as a reminder of mortality and the transient nature of life. They are typically decorated with bones and skulls, arranged in artistic patterns, and are found in various cultures around the world. One of the most famous examples is the Sedlec Ossuary in the Czech Republic, which contains the bones of an estimated 40,000 to 70,000 people. These chapels often attract visitors interested in history, art, and the unique way different cultures approach death and remembrance.